Spots of Diatom Algae yet reading 0 PO4

[Fringe09]

11 month old 200 gallon mix reef tank. 10% weekly water change, skimmer, filter socks, and Chaeto.

Previous feeding routine:
Fish once a day with LRS. Spot feed corals twice a week with a mixture of Reef-Roids and Reef Nutrition Oyster Feast. Daily dosing of Red Sea Reef Energy A&B.

Last Sunday I noticed a few spots of diatom algae on the live rock. Darkish brown and fuzz like.

Stopped Red Sea Reef Energy A&B and started GFO reactor with Rowa-Phos.

Throughout the week tested and Hanna read 0.09, 0.06, 0.02, and now 0.00.

Why does Hanna read 0.00 while I still have algae on rocks?

I thought maybe my Hanna checker or reagent was bad. Tested a sample from my buddy and matched what his Hanna read. So that can't be it.

Besides the why, what should I continue doing or stop doing?

 

[Reeferdood]

Is there a reason you are shooting for zero traits and phosphates? Maybe all you need is a bigger CUC to help you out. Starving your corals is way to much work and the rewards for doing so is nothing, ULNS is nothing more than a PITA...

 

[Fringe09]

Is there a reason you are shooting for zero traits and phosphates? Maybe all you need is a bigger CUC to help you out. Starving your corals is way to much work and the rewards for doing so is nothing, ULNS is nothing more than a PITA...

Not my intention. Just wondering if it’s normal to have a reading of 0 and still see algae.

 

[Reeferdood]

It is possible since the hanna checkers can have errors. Little patches of algae in a system that has low nutrients is normal it just means you don't have enough grazers you keep it in check for you...

 

[Fringe09]

It is possible since the hanna checkers can have errors. Little patches of algae in a system that has low nutrients is normal it just means you don't have enough grazers you keep it in check for you...

I have three tangs who are eating it. Low on turbo snails. Need to buy more.

I'm wondering if I should continue or stop the GFO reactor because of this.

My corals after months have finally started to grow and color up.

 

[Reeferdood]

Keep the phosphate low and nitrates @10-15 ppm. If you need GFO to maintain this then I would keep it running.

 

[Flippers4pups]

From the description, sounds like dinoflagellates, not diatoms. Can you post a picture?

 

[Fringe09]

From the description, sounds like dinoflagellates, not diatoms. Can you post a picture?

I don't even think it's diatom. I think it just brown algae. Below is the best picture I can take. Right of the mili.

 

[MnFish1]

This is meant to be funny actually - not a diss - but why do people use words like 'traits' when 'nitrates' only have a couple extra letters. ....

 

[Reeferdood]

This is meant to be funny actually - not a diss - but why do people use words like 'traits' when 'nitrates' only have a couple extra letters. ....

That is funny. What I find funnier is when someone posts something irrelevant to the topic in forums.
Why do people do that??[emoji848]

 

[GnarcoticFiend]

I don't even think it's diatom. I think it just brown algae. Below is the best picture I can take. Right of the mili.

I have that same stuff in my tank and I don’t think it’s diatoms. Did you ever find out what it is?

 

[Yazannreef]

That looks like diatom algae. Any changes mad week prior that Sunday? It could be due to few things just need to know if they were any slight changes prior. Let me know.

 

[Dan_P]

Not my intention. Just wondering if it’s normal to have a reading of 0 and still see algae.

It is not unusual to see algae with low PO4. The “0” reported by the Checker does not mean no PO4 in the system for two reason. First, the Checker‘s ability to detect PO4 stops above zero PO4. There could be 0.005 ppm PO4 but the Checker would read zero. Second, local concentrations of PO4 might be much higher than the zero in the water. PO4 is not generated equally all over the aquarium by bacteria consuming waste. The algae growth might be associated with areas of particularly productive biofilms.

 

[Paul B]

It's normal, leave it alone. The tanks with all the tweeking are the ones with all the problems.

 

[Salted]

As I'm currently dealing with a diatom outbreak myself (tank about the same age as yours), I'm reading that silicate is a big feeder of diatoms. When's the last time you checked/changed cartridges on your rodi?